generate MIPS32 release 6 ISA instructions
-mips64                 generate MIPS64 ISA instructions
-mips64r2               generate MIPS64 release 2 ISA instructions
-mips64r3               generate MIPS64 release 3 ISA instructions
-mips64r5               generate MIPS64 release 5 ISA instructions
-mips64r6               generate MIPS64 release 6 ISA instructions
-march=CPU/-mtune=CPU	generate code/schedule for CPU, where CPU is one of: